Re: .380 vs 9mm

A .380 is also known as a 9mm "short" due to the casing being a shortened version of the 9mm casing. Bullets are almost identical other than shape. Shorter case means less powder resulting in less distance & accuracy, although for SD encounters the .380 is able to do the job just fine.

They both actually shoot .355 bullets but the 9 mm will shoot any 380 bullet and is capable of using bullets up to about 150 grains, and the 380 will only handle bullets to about 100 grains. Most .380 pistols are blow back actions and have a chamber pressure of 15000 to 20000 PSI while most 9 mm are locked breach design they operate at chamber pressure up to 30000 PSI. Some .380 pistols like the Ruger LCP are locked breach design and that enables them to be made as light and compact as they are, they don't require the heavier mass of the slide to restrain the blow back pressure. While a .380 with proper bullet design is a great CC round for warm weather when people are wearing light clothing however it is only marginal when it is carried in cold weather it would loose much of it's energy while penetrating heave coats and other layers of clothing. The newer compact 9 mm such as the Ruger LC9 are a great choice, they are light, really compact and deliver 9 mm power while being easy to carry.

the recent craze for 380's is due to pocket pistol design
but as small as the 9mm sig 938 and beretta nano is - it may make those 380's obsolete
lets just say the initial cost difference between a ruger lcp and the beretta nano is $120 - that cost will be recovered from the cost of the ammo - about 200-300 rounds which is nothing in the long run (depending on the ammo chosen)

the recent craze for 380's is due to pocket pistol design
but as small as the 9mm sig 938 and beretta nano is - it may make those 380's obsolete
lets just say the initial cost difference between a ruger lcp and the beretta nano is $120 - that cost will be recovered from the cost of the ammo - about 200-300 rounds which is nothing in the long run (depending on the ammo chosen)

I tell you what, there is a significant difference in carrying a nano vs a 380. The Sig 938 is a pretty concealable design but when you absolutely have to conceal a weapon and you want no body to even have a clue, there is no substitute for a .380. There are some places that though it is legal for me to carry there, if people found out they would go crazy especially in todays climate. About a year ago my brother's work called the police on him after some nosy lady was looking through his car and she saw a box of empty 9mm and freaked out. On a good note, his work got severely scolded by the police, they were very pissed and told his work its no reason to call them. Business professionals also seem to like the .380, a lawyer I know carries a ruger lcp.

In Seattle I believe, Mr. Williams in the internet cafe shooting successfully defended himself against two assailants shooting each guy twice with a .380. The robbers barely made it to the hospital. The caliber is adequate

I don't always carry a .380 but when its gotta be out of sight under specific conditions, its the one I go for and I think its the one type of gun that gets carried the most

They both actually shoot .355 bullets but the 9 mm will shoot any 380 bullet and is capable of using bullets up to about 150 grains, and the 380 will only handle bullets to about 100 grains. Most .380 pistols are blow back actions and have a chamber pressure of 15000 to 20000 PSI while most 9 mm are locked breach design they operate at chamber pressure up to 30000 PSI. Some .380 pistols like the Ruger LCP are locked breach design and that enables them to be made as light and compact as they are, they don't require the heavier mass of the slide to restrain the blow back pressure. While a .380 with proper bullet design is a great CC round for warm weather when people are wearing light clothing however it is only marginal when it is carried in cold weather it would loose much of it's energy while penetrating heave coats and other layers of clothing. The newer compact 9 mm such as the Ruger LC9 are a great choice, they are light, really compact and deliver 9 mm power while being easy to carry.

This is a bit off. NATO specs the 9mm at 36,500 psi. +P variants come in at 38,500 psi and there is one +P+ load that registers 42,000 psi.

.380 vs 9mm

Originally Posted by jakeleinen1

I tell you what, there is a significant difference in carrying a nano vs a 380. The Sig 938 is a pretty concealable design but when you absolutely have to conceal a weapon and you want no body to even have a clue, there is no substitute for a .380. There are some places that though it is legal for me to carry there, if people found out they would go crazy especially in todays climate. About a year ago my brother's work called the police on him after some nosy lady was looking through his car and she saw a box of empty 9mm and freaked out. On a good note, his work got severely scolded by the police, they were very pissed and told his work its no reason to call them. Business professionals also seem to like the .380, a lawyer I know carries a ruger lcp.

In Seattle I believe, Mr. Williams in the internet cafe shooting successfully defended himself against two assailants shooting each guy twice with a .380. The robbers barely made it to the hospital. The caliber is adequate

I don't always carry a .380 but when its gotta be out of sight under specific conditions, its the one I go for and I think its the one type of gun that gets carried the most

I couldn't agree more, sir! You are right on target (no pun intended).

A gun in the hand beats two in the drawer.

Originally Posted by jakeleinen1

I tell you what, there is a significant difference in carrying a nano vs a 380. The Sig 938 is a pretty concealable design but when you absolutely have to conceal a weapon and you want no body to even have a clue, there is no substitute for a .380. There are some places that though it is legal for me to carry there, if people found out they would go crazy especially in todays climate. About a year ago my brother's work called the police on him after some nosy lady was looking through his car and she saw a box of empty 9mm and freaked out. On a good note, his work got severely scolded by the police, they were very pissed and told his work its no reason to call them. Business professionals also seem to like the .380, a lawyer I know carries a ruger lcp.

In Seattle I believe, Mr. Williams in the internet cafe shooting successfully defended himself against two assailants shooting each guy twice with a .380. The robbers barely made it to the hospital. The caliber is adequate

I don't always carry a .380 but when its gotta be out of sight under specific conditions, its the one I go for and I think its the one type of gun that gets carried the most

That is the key point in deciding "which is best." The "best one" is the one you actually have with you when you need it. The choice is as much about your own height, weight, and hand-size as the caliber of the bullet. A typical pocket .380 was never a good option for me because my hands are just too big to hold and shoot any of them reliably at a range, much less in an emergency. Adaptations made them usable, but my current Beretta Nano fits my hand fine right out of the box and I can easily hit my target with little effort. It fits me and is with me so it is best for me. It's a poor choice for others like my wife who is just too small to use it. A typical pocket .380 is perfect for her.

Standard 9 mm Piezo electric transducer measurements from center of case is 35000 PSI and +P is 38500 PSI, There is no standard for +P+ loads. Standard 9 mm Piezo measurement from case mouth is 34084 PSI and so is NATO 9 mm measured from case mouth, and they both chronograph about the same from a Beretta 92SF. I tend to load my ammunition to about the same velocity as factory ammo or slightly higher, generally in the area of 30000 to 32000 PSI. There is really no need to push velocity and pressure to the limit, better to go to a more powerful weapon. The original post was about comparing a .380 and 9 mm, most .380 are compact or sub compact pistols, I don't know of any company that recommends more than a limited use of +P ammo in compact 9 mm pistols because it reduces the useful life of the weapon unlike full size pistols that have the extra mass and durability to handle the extra pressure. The +P+ rated ammo is not recommended for use in any compact pistol so it really is not of any concern here.